The construct <link rel="stylesheet" href="main.min.css" /> doesn't raise the HtmlImportSettings.LoadFromUri event on import, as we currently require type="text\css" to be specified explicitly.

When the document contains an image that is defined as an external resource but is not available in the specified location and cannot be found, a KeyNotFoundException is thrown. Handle this exception and replace the missing image with a default one for such cases. Consider exposing an option to notify the user about this error.

When the imported html contains an attribute of the type width="", Wordsprocessing throws ArgumentException and does not import the document. 

Importing an image from HTML with URI as a source, which has applied only width or height and exporting it to PDF (which forces getting the image data so it can be drawn) leads to an incorrect value of 1 (a default value) for the dimension that is not specified.

When the document contains an image with extension, which is not among the supported ones, a KeyNotFoundException is thrown during Import.

An ArgumentException is thrown when importing HTML containing standard and non-standard pseudo classes or pseudo elements. The concreete scenario is the following: 
.myclass::-webkit-scrollbar or .myclass::-ms-expand

The message of the exception is similar to this: "Unexpected character found at position [X]: ".. scrollbar::>>-<<webkit-scrollbar"". 

If HTML document is imported, and it contains image with invalid URL, then the image is imported with this URL in the document model. On subsequent export to Docx, the library tries to download the image data, which throws WebException. Instead, the image should be replaced with generic 'error' image.

Workaround: Manually test the image URL for correctness on HTML import, and replace the data:

        static void Main(string[] args)
        {
            HtmlFormatProvider htmlFormatProvider = new HtmlFormatProvider();
            htmlFormatProvider.ImportSettings.LoadFromUri += (sender, e) =>
            {
                if (!IsValid(e.Uri))
                {
                    e.SetData(File.ReadAllBytes("no-image.png"));
                }
            };
        }

        private static bool IsValid(string uri)
        {
            try
            {
                using (WebClient client = new WebClient())
                {
                    client.DownloadData(uri);
                }
            }
            catch (WebException)
            {
                return false;
            }

            return true;
        }

The current implementation uses System.Windows.Media.Imaging.BitmapImage class in order to take the image pixels for the PDF export. However, BitmapImage class throws NotSupportedException when being initialized with a WMF or EMF image.

WORKAROUND: WMF and EMF images may be converted to PNG images before the PDF export. The following code snippet shows how to convert all inline WMF image to PNG images by using System.Drawing.Image class:

private static void ConvertInlineWmfImagesToPng(RadFlowDocument document)
{
    foreach (ImageInline image in document.EnumerateChildrenOfType<ImageInline>())
    {
        if (image.Image.ImageSource.Extension.Equals("wmf", StringComparison.InvariantCultureIgnoreCase))
        {
            using (MemoryStream wmfImageStream = new MemoryStream(image.Image.ImageSource.Data))
            {
                using (MemoryStream pngImageStream = new MemoryStream())
                {
                    var imageDrawing = System.Drawing.Image.FromStream(wmfImageStream);
                    imageDrawing.Save(pngImageStream, ImageFormat.Png);
                    byte[] pngBytes = pngImageStream.ToArray();
 
                    image.Image.ImageSource = new ImageSource(pngBytes, "png");
                }
            }
        }
    }
}

Table and table cell borders are not evaluated according to inheritance and conflict resolution rules. A conflict will occur when different borders from the table and table cell are overlapping. 

The GetActualValue method of the TableBorders and TableCellBorders could potentially return an incorrect value in some of the following scenarios:

Scenario 1:
A table has cell spacing set to 0. Meaning that the table and table cell borders will overlap.
The table borders have defined all of its borders with border style "Single".
The table cell borders have all of its borders defined with border style "None".

Expected result: the resulting borders should have the border style set to "None" for the location where the table and the cell borders are overlapping.

Scenario 2:
A table has explicitly defined that its right border is with border style "None".
The table has a table style applied with defined border style of type "Single" for all table borders.

Expected result: All of the table borders except the right border should have border style of "Single".

The problem is mostly visible when exporting to PDF and RTF format.